


Temptation So Sweet

by TheDragon



Category: Merlin (TV)
Genre: Alpha/Beta/Omega Dynamics, Bonding, Knotting, M/M, Mating Cycles/In Heat
Language: English
Status: Completed
Published: 2019-02-17
Updated: 2019-02-17
Packaged: 2019-10-30 14:53:24
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 5,871
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17830682
Author URL: https://archiveofourown.org/users/TheDragon/pseuds/TheDragon
Summary: In which there's an alluring smell following Arthur around the castle and Merlin is the source of said smell.





	Temptation So Sweet

**Author's Note:**

> I'm so thankful this fest exists because it got me to finally finish this fic. Also, beware—so much smut lies ahead.

There's been an odd smell wafting throughout the castle all day. It was there the second Arthur woke up and it's been following him around all day. It’s sweet and incredibly enticing, and quite frankly, it's starting to drive him up the wall.

He would normally complain about such things to Merlin, but he's been conveniently absent all day. Arthur is more than half-tempted to go to whichever tavern he'd holed up in and drag him out by his oversized ears, but alas—he's the King, and he has it on good authority (his own) that it's unbecoming to constantly follow Merlin around. Still, though. Merlin has a job serving him, and lately he's been absent more and more often.

He's very much tempted to go look for Merlin and give him a piece of his mind, but the rush of air that accompanies his movement only serves to remind him of the tantalising smell that's been trailing after him. He hesitates for a second, torn between wanting to find Merlin and throttle him, and the desire to find out who that scent belongs to. It's a surprisingly hard decision to make.

After a moment of deliberation, Arthur decides that he might as well follow the smell that’s been distracting him all day. He hasn't been able to focus with it around, and he has _things_ to do, damn it. Merlin can wait a few more minutes.

Oddly enough, the scent seems to lead to one of the rooms within the castle. It beckons Arthur through well-lit corridors and up dusky staircases until he suddenly finds himself standing right in front of the door to Gaius's chambers.

It’s an omega’s heat-smell. He could hit himself in the head for how obtuse he's been, and yet he doesn't. Instead, his hand rises to knock on the door before he fully comprehends what he's doing, but by then it's too late.

No one answers.

His curiosity getting the better of him, Arthur pushes the door open and slips inside.

He may be distracted, but he's nowhere near distracted enough so as not to notice that there's no one in the room—not Gaius, not the omega he'd been expecting to be sitting on the examination table, or maybe waiting for heat-suppressing herbs. There are a few wilted plants lying around, as well as a knife in the middle of a cutting board, and everything looks as though it was suddenly dropped and never again picked up.

He could leave, he supposes, but that tantalising smell is still omnipresent, and since he was planning to look for Merlin anyway, it would probably do to see if he's in his room, if only to yell at him for neglecting his duties.

Arthur doesn't bother knocking as he pushes aside the door to Merlin's room. When he sees Merlin lying on the bed, shaking fit to fly apart, he comes to the one conclusion that he probably should have arrived at long ago.

"What—" he begins, only to be cut off by Merlin's broken whimper.

"Arthur," Merlin groans, sitting up in bed, and it's only then that Arthur gets a good look at him. Merlin's hair is in disarray, his cheeks are flushed, and every single movement of his makes the heat-scent in the room that much more potent. "What. Why're you here?"

"I—" Arthur starts, but he's not sure how to continue, not when he's faced with this... _this_. With Merlin in heat. Merlin, who is supposed to be a _beta_ , smelling like— like—

Like something out of Arthur's rut-induced dreams.

The anger creeps up on him slowly, inching up his spine, curling his hands into fists that grow tighter with every breath he takes, every breath that serves to remind him that Merlin had _lied_ to him, lied for _years_. He was an _omega_ , not a beta. He should never have been in Arthur's service, he should have told Arthur—and how could he have _lied_ to him like this?

Merlin must smell it on him, the anger—or maybe it's the glare on his face that gives him away—but either way, Merlin starts curling in on himself, pulling his blankets up around him as if to shield himself from Arthur's gaze, from his rage.

When Merlin looks up at him, eyes glazed with heat and helplessness and outright _fear_ , fear of _him_ , Arthur's heart just about stutters to a stop in his chest. He takes a step closer to the bed, then another, feeling guilty as his closeness causes Merlin to flinch away and push himself up against the headboard.

Once he's at the head of the bed, Arthur sits down and takes a deep breath.

"Have you taken your herbs?" he asks quietly, tightly, trying to keep the anger, the sense of complete betrayal, the upheaval of his entire _world_ out of his voice. Merlin stares at his as though he's grown a second head, but when Arthur quirks an eyebrow, he's quick to shake his own head no. "Where are they?"

Merlin opens his mouth to say something, but instead of words, the only thing to come out of his mouth is a tortured groan. Arthur watches in concern as Merlin wraps his arms around his stomach under the thin covers.

"Won't do any good," Merlin groans. "Should have. Should have. Taken them yesterday. Didn't have any. Too late now," he finishes with a gasp and leans forward, face marred with pain.

Arthur sits there, unsure of what to do, trying his best to ignore the delicious aroma Merlin's heat is giving off, and how it seems to be growing more and more powerful, more sweet, more _irresistible_ the longer Arthur is there.

Merlin curls up even tighter and sobs into the covers.

It's not panic that drives him out of the room—and if it was, he'd never admit it—but the need to help, the need to take care of Merlin when he's in such a state and there's no one else around to do anything about it. He shuts the door and leans against it, taking a moment to calm down, to let himself think.

First thing's first—he needs to get some food and water into Merlin. Water, especially. Arthur doubts he's thought to take care of himself since his heat started.

There's a bucket of water on the table. He grabs a mug from a nearby cupboard and pours some in. There's not much he can do about the food yet, considering that there's none here, and he can't bring himself to leave Merlin alone for the time it would take to fetch one of the servants and request dinner to be brought in.

He doesn't want anyone else near Merlin right now, either.

Merlin jumps when Arthur comes back into the room, hastily wiping away the tears that had begun to make their way down his face. Arthur walks over to sit down next to him and sets the mug of water on the bedside table.

"Why are you crying?" he asks, reaching out to thumb away one of the tears that Merlin had missed.

"I. I thought you'd left," Merlin replies, his voice breaking on the last syllable. "Thought you were angry. Didn't want to be here. Thought you'd left," he repeats.

Arthur sighs, then picks up the mug.

"Drink," he says, pressing it into Merlin's hands. "You must be thirsty."

Merlin shakes his head and pushes the cup back violently enough that some of the water spills out.

"I don't want it," he says, stubbornly crossing his arms in front of his chest. "I don't need it."

"Yes, you do, Merlin," Arthur growls, losing some of his carefully cultivated patience. "Now drink!" He forgoes passing the cup to Merlin again, half-convinced that Merlin would drop it out of sheer spite, and instead presses it right to Merlin's lips. He moves his other hand to the nape of Merlin's neck to ensure that he can't back away. "Drink," he repeats, voice firm. Merlin's lips remain firmly closed, so Arthur he tightens his grip on Merlin's neck.

Merlin's mouth opens into a soundless gasp, and Arthur uses that to trickle some of the water into it. This time, Merlin swallows immediately, gazing at Arthur with his pupils blown wide, pressing into Arthur's grasp with a soft sigh. Arthur lets the rest of the water flow.

"When will Gaius be back?" Arthur asks, smoothing his thumb over the soft hairs at the nape of Merlin's neck, satisfaction curling in his stomach like a cat when Merlin moans at the feeling, eyes slipping shut. "Merlin?"

"Mmm..." Merlin just barely manages to get his eyes open enough to look at Arthur again.

"Focus," Arthur says, putting the mug back on the bedside table. "Gaius. He's not here. When will he be back?"

"Three," Merlin says, wriggling closer to Arthur, yet making sure that Arthur's hand never leaves his neck.

"Three hours?" Arthur asks. Three hours is fine. He can take care of Merlin for three hours, up until Gaius gets back. And after that, Arthur can take care of himself, because being this close to an omega in heat, to the man he's been in love with for the past few years, is doing _things_ to him, and he can't very much take care of them right now, can he?

Except all of his carefully thought-out plans take a dive out the window when Merlin shakes his head no.

"Three days," he corrects. "Disease. Somewhere. Had to leave." Arthur frowns and moves away from Merlin, startling as Merlin shudders the second they lose skin-to-skin contact.

"He left you here alone this close to your heat?" He and Gaius will be having words about this. Gaius should know better. He's lived with Merlin for years; he must know that Merlin is an omega. And most importantly, he knows _Merlin_ , and how unlikely it is that he would actually bother to care for his own health properly, especially at a time like this.

Merlin shakes his head again, but he's not saying anything more, only scooting forward on the bed until he's almost sitting on Arthur's lap, nose pressed to the crook of Arthur's neck and arms winding around Arthur's waist.

"Merlin!" Arthur yells, scandalised, and regrets it immediately when Merlin pushes away from him, hurt and embarrassment plain to see on his face.

"I'm sorry," Merlin says, sounding completely dejected. "Sorry. So sorry," he repeats, and Arthur feels like an utter ass when tears once again start to flow down Merlin's cheeks. "I'm sorry—"

"Shh, no, shh," Arthur comforts, and after a moment of hesitation, he brings his arms up to pull Merlin into a hug. "I'm sorry. I shouldn't have yelled, not when you're like this."

"Shouldn't yell at me at all," Merlin laughs wetly into his neck, but he doesn't dare to bring his arms around Arthur again, and Arthur finds himself feeling oddly bereft. It's not long before Merlin starts trembling in his hold and starts clutching at his stomach again.

"Merlin?" Arthur asks, panicked, and becoming even more so as Merlin doesn't reply. "Merlin?!" He pulls Merlin's head away from his neck to look at him and see what's wrong, to see if maybe he could help, but Merlin's eyes are shut tight and he's gritting his teeth so hard that Arthur's half-convinced they're going to crack and break into pieces.

"It hurts," Merlin whimpers. "Cramps. Hurts so _bad_." He's crying softly again and clutching at his stomach, and Arthur feels more helpless than he's ever felt before in his life.

"I don't know what to do," he admits quietly. "I don't know how to help you." He runs a hand down Merlin's back, over his sweat-drenched shirt, again and again, and it takes him a bit before he notices his other hand has started curling over Merlin's arse in a very much proprietary manner.

"I hate this," Merlin sobs. "I fucking _hate_ this." He sits still for another second or two, before wrenching himself out of Arthur's grip and grabbing the hem of his shirt.

"What are you doing?" Arthur asks, growing increasingly alarmed the more skin is revealed. He leans back as Merlin wriggles himself out of the blankets and averts his eyes as he starts shoving his trousers down his legs.

"What's it look like?" Merlin asks him bitterly. "It's too hot. My clothes, the bedspread—it's all too _hot_." Arthur feels the bed dip next to him, and he raises his head to look Merlin in the eyes. He's chewing on his lip, which is something he does whenever he's stressed and Arthur hates the way it mars the pink of his mouth with blood. Almost of its own volition, his hand darts out and grabs Merlin's wrist, startling him so much that he stops biting.

"You can help," Merlin says quietly, opting to look at the floor instead of at Arthur’s face. "There's one way you could help."

"Merlin..." Arthur's heart sinks in his chest when he realises what Merlin is implying. "I—"

"No, hear me out. I'll beg you if I have to." The words come out in a rush. "Just. Please. I can't _bear_ this. You can fuck me once and forget about it. Just. It hurts so _bad_."

"I wouldn't want to," Arthur says. Merlin gaze finally lands on him, he looks as hurt and betrayed as Arthur did not ten minutes past. Arthur pushes on, not wanting Merlin to misunderstand what he's trying to tell him. "To forget, that is. I couldn't." He moves his grip from Merlin's wrist and goes for his hand instead, twining Merlin's fingers around his own. "I couldn't bear for this to be a one-off."

For once, Merlin seems to have been stunned speechless.

"You mean..." he trails off, but he doesn't remove his hand from Arthur's grasp. "I—"

"I care for you," Arthur interrupts him, looking somewhere to the left of Merlin's head, avoiding eye contact. "A lot. I have for a while. I just never realised it could... you know. Go anywhere."

 _I thought it was wrong_ , he doesn't say. _I thought it was wrong for an alpha to be in love with a beta. I thought the world look upon the two of us in hatred, in revulsion. I never thought there could be a way for the two of us to be together, even if you somehow returned my feelings._

When Arthur finally deigns to look at Merlin again, the look of shock has been wiped clean off, only to be replaced with something akin to a smile tugging at his lips.

"I care for you, too." Merlin says, squeezing Arthur's hand. "I just didn't think there would ever be a possibility of something happening between us."

"How on earth could you think that?" Arthur asks, just this side shy of outraged. " _Look_ at you. You're wonderful and smart and kind and, and..." he stops, face heating up when he realises that he's said to Merlin things that up till now he's only had the courage to confront in his dreams.

"You think I'm wonderful?" Merlin asks. His eyes are all crinkled in delight and there's a smile on his face—not mocking but genuinely _pleased_.

Gods, he doesn't think he's ever wanted to kiss anyone this badly before.

"Of course I do," Arthur murmurs, just before he leans in and lets their lips meet.

It's like an explosion. Merlin's scent is _everywhere._ His lips are chapped, but that's alright, Arthur doesn't mind because they're soft and sweet. As Arthur presses forward, pushing at Merlin until he's up against the headboard, Merlin finally lets go of Arthur's hand in order to wind his arms around Arthur, one on the back of his head, the other on the small of his back, in an attempt to get even closer to him.

Arthur sucks softly on Merlin's lower lip, then moves to kissing the corner of his mouth. He trails his lips down Merlin's jawline and his neck, until he finally arrives at the place where Merlin’s smell is strongest. He has to hold himself back from biting down on the scent gland, but doesn't manage to keep from marking Merlin with a love bite.

Merlin bucks and moans beneath him.

"Arthur," he whimpers. "Hurry up! I've been in this state since this morning!"

"I never thought I'd live to see the day when I was the one telling you to be patient," Arthur whispers into Merlin's ear, but he obliges to Merlin's request and moves his hands down to the waistband of Merlin's smalls. He gives himself a second to reach in and curl his palms around the globes of Merlin's arse before pulling off the offending item of clothing. "Better?" he asks, his own cock hardening in his trousers as Merlin's smell, now unrestricted by anything, reaches his nose.

"It'll be better once your own clothes are off," Merlin gripes, making to push Arthur's own breeches down his legs. Arthur slaps his hands away before standing up, making Merlin whine at the sudden distance between them. He sits up and moves closer as Arthur starts undressing.

His cock is hard with arousal and the desire to mark and to claim, and it grows harder still the more he watches Merlin, the more he smells him and tastes him. Now that his clothes are off, Arthur moves to get back onto the bed, where he can press Merlin down into the mattress and take care of him properly, but Merlin's hands on his thighs stop him.

Merlin is staring at his cock, eyes dark with lust, and as Arthur watches, he licks his lips.

"Can I?" Merlin asks, moving his head until his mouth is situated right at the tip of Arthur's cock. The warmth of Merlin's breath on his prick makes Arthur shiver with pleasure.

"Gods, yes," Arthur moans, placing a hand on the back of Merlin's neck and winding his fingers through his hair. Merlin opens his mouth and wraps his lips around Arthur's cock, and it's the most wonderful sensation he's ever experienced in his life. Unthinkingly, he pushes down on Merlin's head, shoving him further down his prick. The choking noise Merlin makes at the action both arouses him further and startles him into letting him go.

Merlin backs off, eyes looking straight into Arthur's as his mouth curls into a smirk.

"It's alright if you want to fuck my mouth," he says. "I'd very much like it if you did." And what's Arthur to do when Merlin's looking at him like that, all loving and lustful and finally, _finally_ willing to put his mouth to good use?

So Arthur grasps the hair on the back of Merlin's neck and pushes him down onto his cock. It's slow-going at first as he waits for Merlin to get accustomed to the length Arthur shoves down his throat, but once he's finally got Merlin's lips wrapped around the base of his cock, he wastes no more time. He moves his free hand to join the other one at the back of Merlin's neck and holds him in place as he starts thrusting into him, choking him on his cock.

It's warm and it's wet and it's tight, and sometimes when Arthur pulls out just the right amount, Merlin does something absolutely sinful with his tongue that has Arthur moaning and arching. It doesn't take much longer before his knot begins to form. The swelling at the base of his cock becomes more and more pronounced with each thrust into Merlin's warm mouth. There are tears in Merlin's eyes and on his cheeks, and they're probably the reason he can't see the knot and only realises that it's there when he notices he can no longer take Arthur's whole cock into his mouth, whining in distress. To calm him, Arthur softly caresses his throat, right where he can feel the bulge of his prick.

Merlin, obviously annoyed with he fact that he can no longer fit all of Arthur's cock down his throat, removes his right hand from Arthur's thigh and instead wraps it around his knot.

There's a corresponding warmth in Arthur's groin, and his balls begin to tighten. Arthur starts thrusting faster, chasing after his release. When he feels that he's about to come shoves what he can of his length down Merlin's throat and holds him there as he comes. He watches Merlin as he chokes around Arthur's cock, eyes tearing up as his lungs fight for air.

Arthur doesn't let him go until he's finished shooting all of his seed down Merlin's throat. When he finally pulls out, Merlin coughs and gasps for air, the fingers of both of his hands digging roughly into Arthur's thighs. He looks so fucked out, so delectable, that Arthur can't help but to lean down and kiss him again. He moans when he tastes himself on Merlin's tongue, arousal building up again despite him just having come.

Merlin doesn't fight him as Arthur carefully lowers the both of them to the bed. The smell of his own arousal still permeates the air, and his cock is rock-hard where it is now pressing against Arthur's leg. Separating their lips for a moment, Arthur grinds his thigh against Merlin's erection. Merlin moans and presses closer to Arthur in response, lost in a haze of pleasure and pure, unadulterated _need_.

Arthur lets him do it for a while, pleased that this gives him a chance to mark Merlin up properly. He sucks love bites into Merlin's neck and his chest, some small and pink, others large and dark red in colour. He keeps going until Merlin's front is marred to his satisfaction. Seeing Merlin spread out before him, covered in _his_ marks, wet and leaking for _him_ , makes some primitive, possessive beast curl up in his belly. He wants to fuck Merlin properly. He wants to open him up with his fingers in preparation for his cock. He wants Merlin tied to him, with his knot shoved far up his arse, making sure that none of Arthur's come can leak out and drip down his thighs.

He wants Merlin to be his just as much as he's always wanted to be Merlin's.

Arthur is shaken out of his own growing haze by the sound of Merlin whimpering in need, repeating his name over and over and _over_ again.

"Arth— Arthur. I can't. Need to fuck me. Can't come like this," Merlin sobs, spreading his legs wide. "Please, Arthur. _Please_. It _hurts._ " As he watches, Merlin moves his fingers down to his own arse, covering them in rivulets of slick as he strokes them over his hole. " _Arthur_ ," Merlin whines again, voice cracking near the end. "I need your knot!"

Arthur's body is moving before his mind has fully comprehended what's going on, seemingly unable to get over the fact that there's an omega lying on the bed beneath him, begging him to fuck him through his heat. Within a split second, he has Merlin's arms pinned over his head and is moving his other hand down between Merlin's legs, where it can  _finally_ get to his wet hole. He runs a finger over it once, in warning, then slips it inside. The finger goes in easily, covered with Merlin's slick.

Merlin squirms a little in Arthur's grasp. He has an expression on his face as though he isn't sure that he likes the penetration, even if it's exactly what his body is begging for. Arthur kisses the uncertain twist of his lips and moves his finger a little, looking for Merlin's prostate.

He knows the instant he finds it, because it has Merlin's back arching and a gasp tearing itself out of his mouth.

"M-more," Merlin demands, and Arthur obliges. He removes one finger, only to lunge back in with two, stretching Merlin just a bit further. He strokes them in and out a few times, trying to get Merlin accustomed to the feeling of having something in his arse, then changes two fingers to three. Merlin's hole accepts them easily, takes to being fucked like it was made for it.

By the time Arthur deems Merlin ready, his own cock is begging for attention, for access to Merlin's deepest reaches. He pulls his fingers out, gives himself a moment to admire the reddened gape of Merlin's slick hole, before grabbing him by the hips and turning him over until he's face down on the bed, cock rubbing against the sheets. Merlin whines, then lifts himself to his knees and spreads his legs, giving Arthur unfettered access to his wet hole, offering it up to him like a gift.

And it _is_ a gift, one he'd never thought he could have. Even if Merlin changes his mind once his heat is over, Arthur will never forget this moment.

He smooths a hand over Merlin's back in praise, then uses that same hand to spread the cheeks of his arse. Merlin's hole is gaping invitingly, twitching every so often, just waiting to be pierced by Arthur's prick. As Arthur presses the head of his cock to it, Merlin stutters forward on his hands and knees.

"Easy," Arthur says. He reaches down to tug at Merlin's cock, trying to get him to think about something other than the fact that he's about to be impaled on Arthur's prick. Merlin moans, long and low. The sound has Arthur's own cock twitching, and he finds he can't help himself anymore. He holds Merlin still with one hand wound tightly around his cock and the other on his hip, and drives himself forward steadily.

Merlin squirms under him as he sinks past the initial resistance, back arching to move away from Arthur, away from the sting of something larger than fingers being shoved into him. Arthur holds him down and keeps pushing forward until all that's left outside of Merlin is Arthur's knot. It's hot and tight and wet and completely overwhelming— _so_ much better than Merlin's mouth.

He stops himself from moving, opting instead to wait for Merlin to get used to the feeling of being stuffed so full.

"A-Arthur," Merlin whines, turning his head to the side to look at him. His eyes are completely glazed over, lips red and bitten raw. "Arthur. Arthur. _Arthur_."

"I'm here, Merlin, I'm here," he replies, winding his hands around Merlin's waist, eager for more skin-to-skin contact. "I've got you, love." He bends to cover Merlin's back with his own chest and starts pressing kisses to his shoulders, his neck, the side of his jaw; everywhere he can reach. Merlin lets him do it, even leans his head to the side in submission, bearing more of his neck, bearing his _mating gland_ for Arthur to bite down on so he can breed him properly.

"Fuck, oh fuck," Arthur chants when he notices Merlin doing it. His hips shove forward of their own accord, knot pressing dangerously against Merlin's rim. "Don't do that," he pleads. "You're in the middle of your heat; you'll regret it when it's over."

"I won't," Merlin says, sounding completely and utterly convinced of what he's saying, if a bit breathless. "I've been wanting this for _years_. I don't think there's ever been anything I've wanted more."

"Merlin," Arthur moans. Merlin shoves his hips back, trying to get Arthur to start moving, and Arthur is in no state to contend with his wishes. "You'll ruin me. This will ruin me for everyone else. I hope you realise that."

" _Good_ ," Merlin growls as Arthur finally starts thrusting. "Because no one else can have you."

As Arthur begins to fuck him more roughly, Merlin starts making these delicious noises, almost like the breath is being forced out of him every time Arthur drives his cock into Merlin's tight heat. It's like the loveliest song, and Arthur wants it to never end. He wants to spend eternity here, with Merlin below him, body bared and welcoming. He could spend forever listening to all the soft sounds Merlin makes, watching how his body arches as Arthur's cock glides over his prostate again and again, smelling Merlin's heat-scent, just like and yet also somehow _more_ captivating than what he normally smells like.

He places his teeth right over Merlin's mating gland and just _breathes_.

"Just fucking _bond_ with me already!" Merlin complains, pushing himself closer to Arthur, making him groan as the scent nears his nostrils.

"Promise me you won't regret it," Arthur pleads. "Promise me that tomorrow, you won't declare this to have been a mistake." He's being vulnerable; he _hates_ it. And yet, Merlin is the only person around whom he can allow himself to be like this. After all they've been through, he knows that Merlin will never mock or reject or hurt him. He _trusts_ Merlin.

He _loves_ Merlin.

"You know I won't," Merlin whispers softly, turning his head to look Arthur right in the eyes. "I love you."

Despite Merlin's heat, despite his own rut, Arthur can feel his eyes getting wet, so he quickly ducks his head so that Merlin won't be able to see. His heart feels like it's going to burst in his chest, and doesn't recall there ever being a time when he was this happy.

"I love you, too," he whispers into Merlin's skin, right before opening his mouth and sinking his teeth into the soft spot between Merlin's neck and shoulder. Merlin howls beneath him, long and drawn out, as Arthur presses down onto the gland as hard as he can. The responding surge in his own body is instantaneous, leaving him feeling as though he's floating somewhere high above the ground.

Merlin shudders in his grasp, then grows slack, letting Arthur do with him as he pleases.

He can feel his knot growing again, hitting the rim of Merlin's hole on every thrust, threatening to slip in every time Arthur grinds his hips against Merlin's. Any larger and it won't be able to fit. Any larger, and they won't be able to mate properly.

With that thought, Arthur slows his movements and moves his hips in a way that he instinctively knows will put just the right amount of pressure on Merlin's hole and force it to accept Arthur's knot. It's a slow-going process at first, and it must hurt Merlin, having something so large pushed inside his once-tight hole, but it's what they both crave, what they _need_.

They both groan once the knot finally pops in, growing larger as it ties the both of them together. Arthur's balls draw up and he holds Merlin down as he comes inside him. Merlin follows Arthur over the edge, not even needing a hand on his cock to help him succumb pleasure.

Every contraction, every clench of Merlin's hole has more come spurting out of Arthur's cock, until he's certain that it's too much, that no more will be able to fit inside him—and yet, Merlin doesn't complain. He melts into the bed, completely boneless. Arthur holds him close and places his hand right over Merlin's beating heart, if only to prove to himself that this here, what they're doing—it's _real_.

Once he's ascertained that Merlin can't go anywhere, Arthur finally removes his teeth from Merlin's skin and admires the mark. There's some blood, but that's to be expected. It should heal and leave behind a visible imprint of Arthur's mating bite, and then no one will even be tempted to try to separate Merlin from him. Not that he thinks Merlin would leave him for anyone else; he just doesn't want people thinking that Merlin is available and they're welcome to try to lure him away.

"You're amazing," Arthur groans into Merlin's ear, suddenly overcome with affection for him. "Perfect. You're perfect."

Merlin turns his head around. His lips are pulled into a wide, satisfied smile, and his eyes are crinkled around the corners. He moves one one of his arms back and places his hand on the back of Arthur's head, pulling him down for a breathtaking kiss.

"These might be the only sincere compliments I've ever gotten from you," he laughs, and Arthur can't fight the grin that appears on his face.

"They are _not_ ," he protests half-heartedly, nuzzling his face into Merlin's. "I compliment you all the time."

"Sarcastically," Merlin points out. He's still laughing softly, holding Arthur's head close, and Arthur doesn't think that he's ever been happier. He gently eases off of Merlin, then turns them both so that they're lying on their sides, legs tangled with each other's.

"How's your heat?" Arthur asks, needing to make sure that Merlin is as fine as he seems. Merlin hums.

"Much better now. The cramps are gone and I don't feel so hot anymore. It'll probably be back soon, though," he says apologetically.

"You say that like it's a bad thing," Arthur complains.

"Yes, well, we're going to be pretty much holed up here for the foreseeable future. The next week at least. It'll be hard to run a kingdom while you're stuck here with me," Merlin says. A second later, his expression becomes more reserved. "That's. I mean. You will be staying?" he ascertains, hunching in on himself and looking at everything but Arthur's face.

"We're mated now. I just told you I love you. Do you even have to ask?" Arthur tells him, swatting at the top of Merlin's head. "Of course I'm staying with you. And you don't have to worry about the kingdom; there's protocols in place for this reason exactly."

"Right," Merlin chuckles breathlessly. "Sure. I knew that."

"You're thinking too much," Arthur says, then proceeds to lean down and kiss Merlin so thoroughly that he loses all of his remaining brain function.

"Yes, well, maybe you're not thinking enough." Merlin licks at his lips, eyes dark. He shoves his hips back roughly and Arthur swears. "Then again, it must be hard for you to think when you're stuck so deep inside me. Tell me, Arthur—what's it like?" He starts to rhythmically clench his hole around Arthur's cock, causing Arthur to moan with pleasure.

"So good Merlin. You're so tight and wet and hot and I can't. Get. _Enough_." He tries to still Merlin's movements with a hand on his hips, but it proves to be a fruitless effort. Merlin keeps shoving back more and more roughly, fucking himself on Arthur's cock, on his knot, and _fuck,_ how is Arthur meant to hold himself back when Merlin's behaving like a complete and utter _tart_?

So he doesn't. He turns them both over and goes right back to grinding into Merlin's tight heat, holding Merlin's arms above his head so that he can't pleasure himself, not until Arthur's had his second release. Merlin screams when Arthur finally lets him come.

When they're done, they collapse on the bed in exhaustion. Merlin is panting, completely worn out. He pulls Arthur's hand over his waist and snuggles into him, sated for the time being.

Arthur presses his forehead to the back of Merlin's neck and lets him sleep.


End file.
